This proposal is responsive to RFA-CE-12-007, pertaining to research objective #5: to assess the health impact of a state Prescription Drug Monitoring Program. Unintentional drug poisonings-overdoses-have drastically increased over the past decade. Because much of this increase has been associated with increasing abuse of prescription opioid medications, policy tools like Prescription Monitoring Programs (PMPs) have become an important part of statewide strategies to prevent prescription drug diversion, promote safer prescribing of abuseable medications, and ultimately reduce opioid overdose mortality. PMP use may alter overdose mortality, if used widely, as intended, and to their full potential. However, it is unknown how PMP use may impact other nonmedical prescription opioid use behavior, may influence population dynamics of subpopulations of users and nonmedical users, may alter local availability, and may affect street price. The overarching goal of this proposal is to evaluate the health impact of PMP utilization by prescribers and pharmacists as a means of preventing unintentional prescription drug overdoses in the adolescent and adult population. Analyses will focus on PMP utilization at the local level in 7 study states with varying PMP profiles and overdose burden and high coverage rates for outcomes: New Mexico, Oklahoma, Michigan, North Carolina, Maryland, Missouri, and Tennessee. Specific aims are to: 1) Create taxonomies for further evaluation of PMP use characteristics in study states by critically reviewing: a) laws and regulations governing the use and access of the state PMPs, and b) PMP data on prescriber, pharmacist, and law enforcement use; 2) Test the effects of PMP presence, local coverage (proportion of professionals registered for PMP use at 3-digit ZIP code) and local use (PMP query volume at 3-digit ZIP code), controlling for population factors, on local markers of demand (use and nonmedical use, predefined typologies of prescription opioid use, street price), supply (prescribing patterns, morphine-equivalent dose dispensed, source of prescription opioid), and harm among nonmedical prescription opioid users (route of administration, initiation of heroin use, nonfatal overdose); and 3) Assess state PMPs' (n=40) current prescription opioid overdose prevention education and programming efforts and examine specific state or community delivery mechanisms for future targeted interventions. Drawing upon data available from 2009 to 2012 at the 3-digit ZIP code level from three unique sources - state PMPs, a novel online street drug pricing index, and a national, real-time, surveillance dataset that captures prescription opioid use and nonmedical use from adults being assessed for substance abuse treatment-the core analyses proposed in this study will answer timely research questions of national public health importance. This proposal addresses the Healthy People 2020 focus area(s) of Injury and Violence Prevention and is in line with the NCIPC's performance goal to conduct a targeted program of research to prevent injuries and violence, and reduce their consequences.